How to show curve vertex tilt + radius value slider in custom toolshelf panel
Unfortunately the content of that Transform panel are defined outside of the Python api. But you could have something monsterously convoluted like this to show up the Tilt value of a single selected Control Point of a bezier_point

    if context.active_object:
        if not context.active_object.data:
            pass
        else:
            # you do more checking here to verify the kind of active_object 
            # I will ommit this from the example. 

            data = context.active_object.data
            points = data.splines.active.bezier_points

            selected_points = [idx for idx, p in enumerate(points) if p.select_control_point]
            print(selected_points)
            if len(selected_points) == 1:
                idx = selected_points[0]
                point = points[idx]
                col = layout.column()
                col.prop(point, "weight_softbody", text='weight')
                col.prop(point, "radius", text='radius')
                col.prop(point, "tilt", text='tilt')


This approach only works when 1 point is selected, i'm sure it's possible to adjust the mean value too but it's more complicated, and might involve writing your own operator -- I haven't looked very deeply.